1. Technical Field
The disclosure relates to a cable connection structure and an endoscope apparatus.
2. Related Art
In a medical endoscope, an insertion section is inserted deep inside a body for observation of a lesion, and further a treatment instrument is combined if necessary to inspect and treat inside the body. Such an endoscope includes an image sensor such as a CCD at a distal end of the insertion section, and outputs data from the image sensor to an external control device or the like, through a cable connected to an electrode on a substrate. The endoscope has a distal end portion bendable upward and downward, and rightward and leftward owing to connection of a bending section bendable in a plurality of directions, but a stress is applied to a connection portion between the electrode and the cable due to the movement of the bending section, and the connection portion is required to have a high adhesion strength. Commonly, when a large load is applied to the connection portion, the electrode to which the cable is connected is separated from the substrate. Therefore, a technique for improving the connection strength between the electrode and the substrate has been longed for.
As a technique for improving the adhesion strength between the electrode and the substrate, a technique is disclosed for forming a solid solution including copper and nickel, on an exposed surface of a via formed in a substrate and including a high melting point metal, to improve the adhesion strength to an electrode mainly including copper (e.g., see JP 2009-158668 A).